Pollution characteristics and spatial distribution evaluation of the health risk of heavy metals in an electroplating plant site

Taking an electroplating site in Suzhou City as the research object, the pollution degree of eight heavy metals (As, Cd, Pb, Cu, Ni, Zn, Hg, Cr(Ⅵ)) in soil samples was evaluated by using Nemero index method, and it was clear that the soil of the electroplating plant was polluted by Ni and Cr(Ⅵ). Based on the health risk model and Kriging interpolation method, the three-dimensional spatial health risk distribution of Ni and Cr(Ⅵ) in soil was studied. The results showed that the carcinogenic and non-carcinogenic risk levels of Ni and Cr(Ⅵ) in Workshop Four (rack plating of nickel and chromium) exceeded the acceptable threshold. The pollution of Ni and Cr(Ⅵ) showed a pattern of point source diffusion. The farther the distance from Workshop Four (polluted area), the lower the pollution degree. From the vertical perspective, both Ni and Cr(Ⅵ) presented the behavior of migration from the surface to the deep soil. Therefore, it was necessary to remediate the soil before development and utilization.